Remedial English

Words that sound kind of alike, but are not, in fact, interchangeable:

Prostrate and prostate.

Ethic and ethnic. (Ethnical, in case you wondered, is not a word. Please don't use it.)

Also:

Sense and since.

Effect and affect.

And wright, while a possible proper noun, is not a verb. Alas.

Along similar lines: Why would one need to specify that something is a "big fire hazard".

Is there such thing as a small fire hazard? (Just a little one, no big deal.)

Please review the above. There will be a short quiz.

Thanks.